Consonants

This video just has a plain transcript, not time-aligned to the videoConsonants are speech sounds that are made with some degree of constriction in the vocal tract.
Phoneticians define consonants according to three articulatory dimensions:
Voice,
Place, and
Manner
This video will introduce you to each of these terms and provide some examples of sounds that differ along each dimension.
VOICE
The first parameter, voicing, is presented as a binary option in the IPA chart. It is either on or it’s off; voiced or voiceless. If a sound is voiced, that means that it is produced with vibrations of the vocal folds. A voiceless sound, on the other hand, will not be accompanied by such vibration.
Here is an example of a pair of sounds you are probably familiar with that differ only in voice: [s]/[z] from seeing speech
It is difficult to see voicing differences in the video because the vocal folds are very small and hidden away inside the larynx. You can experiment with voicing in your own vocal tract in the following way:
Place your hand on your throat and make a prolonged [ssssssss] sound.
Now, keeping your hand on your throat, switch to a [zzzzzzzz] sound.
(!) If you’ve never done that before, you might be a bit surprised at what you just felt. That buzz in your throat is your vocal folds giving you a voice.
The IPA only distinguishes between two voicing modes in the main consonant chart, but phoneticians recognize at least 2 further modes of phonation:
Breathy
Creak
In order to indicate Breathy voice or Creak the IPA provides diacritics that can be applied to a symbol to modify its usual interpretation. (Here, a voiced b becomes breathy voiced b, and a vowel with regular phonation becomes creaky voiced just with the addition of the diacritic.)
PLACE
The next parameter is place of articulation, often referred to simply as “place” for short. Place of articulation tells us where in the vocal tract the constriction is taking place, and is named for the passive articulator at that place.
For example, you can make a closure between your tongue and your upper teeth, or the alveolar ridge behind your teeth, or the hard palate, or the soft palate, just to name a few.
Places of articulation are given adjectival names which are taken from the nouns that name the articulator. So if the place of articulation is at the lips, they would be called labial sounds. A closure at the alveolar ridge would be called alveolar, and a closure at the velum or soft palate, would be called velar.
Knowing the names of anatomical structures in the vocal tract will help you to remember the names of places of articulation as well.
MANNER
The third parameter for describing consonant articulation is manner, which describes how much constriction is present in the vocal tract during production of that consonant. The IPA lists 8 manners of articulation in the main consonant chart, ranging from complete closure to mere approximation.
In most cases, the tongue is the active articulator whose actions are being described by the manner of articulation, though there are some exceptions to this.
A complete closure of the vocal tract is known as a plosive or stop because the closure completely stops the airflow.
It is also possible to have a complete closure in the mouth, while the velum is lowered to allow air to pass through the nasal cavity. These sounds are called nasals or sometimes nasal stops.
Another manner that is similar to a stop is a tap or flap. In this case, the active articulator, usually the tongue, makes a quick contact at the place of articulation without maintaining the closure for any appreciable period of time.
A trill is similar to a tap in that it involves quick contact with the place of articulation, however, the contact repeated many times in rapid succession as the result of the articulator vibrating in the force of the airstream, much like a flag waving in the wind.
Another way to constrict the airflow in the vocal tract is to create a narrow passage between active and passive articulators. By forcing air through this passage, a noisy, turbulent, hissing sound is produced that is known as a fricative.
In most cases, the narrow passage that is formed for fricatives is located along the center line of the mouth and tongue, but the tongue can also be held with a closure at the alveolar ridge and passages along one or both sides of the tongue. Such sounds are called lateral fricatives because they are produced with airflow out of the sides rather than down the middle of the vocal tract.
Finally, the most open consonant articulation is known as an approximant, because the articulators do not make direct contact with one another, nor do they cause turbulent airflow. As with fricatives, approximants may be central with airflow proceeding out through the center of the mouth, or lateral with the airflow passing out around the sides of the tongue.
NAMING CONSONANTS
The three parameters voice, place and manner also provide us with a means of naming consonant sounds.
Each of the parameters is independent of the others, so in principle, you can combine them in any permutation you like. However, as we will see when we look at the IPA consonant chart in detail, not all combinations of these parameters are useful for describing the sounds of actual speech.